Hello guys,i have a tuned Seicento 1.2 8V MPI(Punto 75 engine) with camshaft 282 degrees lift duration 10.68,4-2-1 headers and 48mm exhaust and pipe,higher compression than stock - 10.5 (skimmed head and engine block)

Got the car on a SuperFlow dyno and only saw 77,7HP and 110NM on the crankshaft..that means only 2,7HP and 4NM more more over stock.With all the mods i have done i should get at least 85HP.But something is wrong....

We use the Seicento Mpi 1.1 plastic manifold(with 40mm TB) instead of the Punto 75 manifold.I heard that the Punto 75 manifold has a lot bigger inlet ports than the plastic 1.1 manifold,so can this cause all this power loss???

*The engine is also rebuilded and the Ecu was remaped on the Dyno.

I'll be following this with great interest.

First of all, I agree with you. A hotter cam in a P75-engine should deliver more power than that with a properly mapped ECU.
Second, my engine is an 1108 SPI with similair mods (280/260 degree C&B cam, 2" exhaust) and was somewhere around 85HP on 98 octane fuel when it was in max trim. No idea of its power now, but will find out some time over the next month or so.

Of course there will be different results on various dynos at different altitudes and so forth, but that does seem rather low.

If fuelling (lambda/O2-readings) are good and there are no leaks, I'd think either the remap's ignition timing isn't right or the cento inlet is in fact so restrictive, thus my interest in this topic.

My ECU has a Chip2Race at the moment, I think. I have the chip for 98 octane on a shelf but the previous owner of the car ripped it out and I'm not keen on soldering it back in myself, TBH.

1. The stock P75 engine is actually 73hp.

2. The exhaust is way too big for a 8V n/a engine IMO and probably counter productive as far as power is concerned.

3. Which ECU is this? (Depending on the answer I might also suspect a poor tune)

Can you upload the dyno printout?

2) It is 48mm out and 45mm in so it is not that big for a quite well tuned 1.2 8V engine.

3) Ecu is Magneti Marelli - The big one(not micro) - My car is a Seicento Sporting 2002 MK2(MPI).

Here is the dyno printout :

http://oi61.tinypic.com/70vzwx.jpg

Ad. 2 perhaps not, but I personally think people go overboard with exhaust diameters (myself included).

The bottom line about the ECU is that it is an MPI ECU and I expreseed my doubts about common tuners knowledge about this ECU enough many times, see for example my discussion with thunderfox in cc1's New Era thread.

woj said:

Ad. 2 perhaps not, but I personally think people go overboard with exhaust diameters (myself included).

The bottom line about the ECU is that it is an MPI ECU and I expreseed my doubts about common tuners knowledge about this ECU enough many times, see for example my discussion with thunderfox in cc1's New Era thread.

Click to expand...

Tell me exactly what you mean about these ECUs and the tuners.The Tuner has done remaps on hundreds of Marelli ECUs,he is only tuning Fiat-Lancia-Alfa Romeo Ecus and he is well know in Dragster Racing here in Greece.Two months ago he did a remap on 1.2 8v Cinq which was using the micro ecu.

The big question is :

Couldn't it be the Inlet Manifold???

Regarding the power curves:

Doesn't torque peak rather early, considering it's kind of a hot cam?

I'm asking because I don't know any better.

I am not doubting your tuners experience, but:

1. Have you seen that other's CC 1.2 before and after results? Was it remeasured after some weeks after the ECU fully adapted? What were the mechenical mods?

2. Using this ECU for a 1.2 engine requires reconfiguring the knock sensor setup from 1.1 engine to 1.2. This is 10+ maps and parameters on this ECU for starters. Without this the knock prevention routines get possibly false feedback and mess with the ignition timing. This would be just one example of "knowledge". Tuners commonly use map information provided by tuning programs and databases that they buy, and these I am afraid are often far from perfect or complete. Such ready to buy information for this particular ECU provided by the ECM program for example is pure crap as far as proper tune is considered.

And no, I do not know the real reason for your power problems I am afraid

I doubt if the inlet manifold is responsible.

I'd be inclined to go aftermarket ECU (Det3 is probably going to be cheapest, then DIY Megasquirt) and play with the cam timing.

The big advantage of the aluminium intake manifold is that it's easier to mess with if you've access to TIG and that it'll take a wider range of injectors than the pico style (plastic MPI) ones. (You need to re-locate the servo take off anyway to get it to fit -- Palio ones are said to have the take off in the right place.) But there are still going to be issues around the return/non return fuel delivery system.

Sorry but i forgot to mention something really important.

We made a custom adjustable cam vernier pulley so that we can run the Punto 75 engine with knock sensor as the 1.1 Sei MPI engine does,and we did it.

So,it is not the cam timing.The cam timing is just fine.

With other words we have a Punto 75 engine running with knock sensor.

Here it is :

http://oi58.tinypic.com/21oy13a.jpg
http://oi58.tinypic.com/21b4275.jpg

The aluminium intake on the Punto/Palio has shorter ducts and they seem to be a bit larger. I'm still looking into using one on my engine with an adaptor plate to fit a Marea 46mm TB. You can use the plastic fuel rail with short hi z injectors but spacers are required under the rail mountings.
Looking at your RnR print out, There seems to be a lot of erratic peaks and troughs in the curves. Maybe the Ecu is fighting to correct some issues as woj has said?
This is my printout. At 4000-4750rpm, mine was having unknown ignition problems as can be seen on the curve but it is the best that can be done for now.

slightly off topic mate, how much did noble charge you for a power run?

hf turbo said:

slightly off topic mate, how much did noble charge you for a power run?

Click to expand...

The full setup and map was £550. I think I saw them advertising 1 run at £38 but please don't quote me on that. lol. Give them a ring.

I'll wait for the turbo conversion before i go for the whole set up espcially at that price, however a if it that much for a power run i might be up there pretty soon.

cheers CC1

Guys,please don't go off topic!

I found this...https://www.fiatforum.com/cinquecento-seicento/231079-why-wont-1-2-8v-mpi-sei-give-75hp.html
and now i am sure it is the inlet manifold.
You can even see the difference in ports from the pictures.

But,i have a last question.Should i leave the Punto 75 TB stock(38mm) or Bore it out to 42mm?I am going to use a dexcraft induction kit.

What do you think?

I'd say, unless you've access to a flowbench (and the ability to interpret the data) just try the P75 inlet mani (etc) as stock until you have RR figures to back up the idea that it it works.

Try and get the Palio one (unless you have someone with a TIG who'll modify the P75 one for free).

Let us know how you get on.

If tuning we're simply a matter of making all the holes bigger, we'd all be experts!

fingers99 said:

I'd say, unless you've access to a flowbench (and the ability to interpret the data) just try the P75 inlet mani (etc) as stock until you have RR figures to back up the idea that it it works.

Try and get the Palio one (unless you have someone with a TIG who'll modify the P75 one for free).

Let us know how you get on.

If tuning we're simply a matter of making all the holes bigger, we'd all be experts!

Click to expand...

I have two questions :

1)What is a TIG and what do i need to modify on the P75 manifold?

2)What are the differencies between the Fiat Palio 1.2 8V manifold and the P75 manifold?Are they different?Because both cars have the same engine and both have metallic manifolds.

The take off for the brake servo on the P75 inlet gets in the way in a cento so needs to be modded and fitted to the side, like the one I have spare. I believe the Palio has this on the side already instead of the rear.

Cento186 said:

The take off for the brake servo on the P75 inlet gets in the way in a cento so needs to be modded and fitted to the side, like the one I have spare. I believe the Palio has this on the side already instead of the rear.

Click to expand...

Thanks but "i believe" is something 50/50 and not enough.We have to be 100% sure that the palio one already have it on the right side,otherwise there is no reason in getting the Palio mani instead of the P75,one.
So,did anyone see it with his eyes that the palio one is diferrent and is the one we need or we are talking theoriticaly?
I found a palio manifold but he is far away from me to check if the manifold differs from the P75 one,so i need someone 100% sure that this is the one i have to buy and not the P75 mani.